our legal team. Nancy grace, the host of nancy grace on hln. Legal analyst, dan abrams. Dan, I'm no lawyer. But I don't understand what jeffrey pyne's lawyer was doing to the lead detective. He's been asking a number of people. And he's been meaning it to be a rhetorical question. You can't say for certain who did this. Or who killed her. But it's -- lawyers know you should never ask the question if you don't know the answer. Particularly, when you're talking about a detective, who clearly believes, based on all of the evidence, that he does know, who did it. So, it was not a smart question to ask. Not going to be the game-changer in this case. But in retrospect, the lawyer shouldn't have done it. Nancy, you would think that the detective does believe that jeffrey pyne's guilty, after the whole investigation, or there wouldn't be a prosecution. But that has to have some impact on the jury. Of course it does. Very typically juries believe police officers. They believe doctors. Often, you'll see a doctor come in his surgical outfit because juries believe people in positions of authority, that they have trusted throughout their lives. And of course, they typically should. It's more than just a bad question. If the state had asked this question, it's the reversible error. It's asking a witness to the ultimate issue, that being guilt or innocence. And to ask a detective that question was crazy. But here's where I think the tide is turning. And don't get me wrong. I don't have a dog in the fight. All right? Because if someone had beaten my child since age 9, they might just get the death penalty. And I'm talking about ruth pyne, who had attacked her children, tried to strangle them, since they were little children, with a mental illness. But this is where the tide is turning. He places himself in the home at the murder scene at 1:30. There's a 1 1/2-hour window. After he leaves the home, an unknown assailant comes in and kills the mother? Also, he's got blood, ruth pyne's blood water faucet. Somebody tried to cleanup. That's not a random killer. And look at what's missing. You talked about it in the studio. A box cutter, she was stabbed in the neck. A screwdriver, she was punched in the neck, and a two by four. What robber would have taken those things? But what they didn't say in opening statements is the result of the skin under her fingernails and the hair in her hand. That's going to tell the story. I think the tide is turning against him. Still, I say jury nullification. I agree with nancy with regards to the hair. If you have his hair in her hands, I don't know how he's going to explain that. I don't think we're going to hear that sort of evidence. We shall see. But the evidence is piling up. Is there any way now for jeffrey pyne to move back to what a lot of people thought he might have argued in the first place, that this was self-defense? There's no way for him to overtly argue that. What his lawyer wants to do is offer subtle undertones throughout the case, reminding jurors, without saying it, you know what? Even if you think that he did this, even if you think he might have done this, this isn't a case where you want to convict here. And I think, yes. There is evidence that it's piling up here. But I don't agree with nancy it is so crucial that he was overheard saying he was at the house at 1:30. People get times wrong all the time. He could very easily claim, why would I possibly have wanted to put myself at the home at the exact time that I knew that i had just killed her? Why would I do that? I think that's something that you can explain away. Probably tried to cover his tracks. Another thing we heard about are the phone pings. His cell phone placed him there. There's so much evidence they did not set for in the opening statement. And if it's not, their goose is cooked. It's over. There's going to be a not guilty. A lot more evidence to come. We'll have you back. Time, now, for the weather. Sam champion on his way to help

This transcript has been automatically generated and may not be 100% accurate.

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